Final Exam - Reflection

Please answer the following question as best as you can and your answers should be thoughtful and complete.  

Example: 

Question: What is dark matter?

Answer 1: Dark matter is theorized to exist and has no interactions with light, meaning that we can't see it. Also, it hasn't been proven just yet and we only have indirect evidence to support its existence. (Feedback: The response is thoughtful and in complete sentences. Full credit awarded)

Answer 2: Can't be seen (Feedback: The response is not thoughtful and is not a complete sentence, No credit awarded)

Answer 3: Dark matter is a failed star. It is dark as it does not give off any light. They are very hard to find and are virtually undetectable. (Feedback: while the response was thoughtful and used full sentences, the science was incorrect. No credit awarded)